Diffuser



Dec. -30, 1941.

C. P. BRlDGES DIFFUSER Original Filed Jan. 24, 1936 2 Sheets-Sheet 1 Dec. 30, 1941 C. P. BRIDGES DIFFUSER Original Filed Jan. 24, 1936 2 Sheets-Sheet 2 Patented Dec. 30, 1941 DIFFUSER. Charles P. Bridges, Dedham, Mass. Original application January 24, 1936, Serial No.

60,611. Divided and thi 1939, Serial No. 259,377

1 Claim. ,(01. 98-40) This application is a division of application Serial No. 60,611, filed January 24, 1936, which has matured as Patent No. 2,152,238.

The present invention relates to the treatment of material, more particularly to the absorption of moisture from, or the addition of moisture to, web material, and more specifically to diffusers through which conditioned air is distributed to the web material.

The principal object of the invention is to produce a diffuser, by which a rapid, uniform and even conditioning throughout the web of material is insured.

To the accomplishment of this object, and such others as may appear hereinafter, the various features of the present invention reside in certain constructions, combinations and arrangements of parts, all described hereinafter and then set forth broadly and in detail in the appended claim.

The various features of the present invention will be readily understood from an inspection of the accompanying drawings illustrating the best form of the invention at present known to the inventor, in which,

Figure 1 is a view in elevation of the diffuser;

Fig. 2 is a detail view in sectional plan taken along the line 2-2, Fig. 1;

Fig. 3 is a detail view in sectional elevation taken along the line 3-3, Fig. 2, and

Fig. 4 is a diagrammatic view in plan, partly in section, showing the relationship of the diffusers to the web of material.

The present invention may be embodied in a standard tentering frame, along which the web of material travels in a plurality of passes. In the drawings, the tentering frame is merely indicated, as it forms no part of the present invention. Referring to Fig. 4, the tentering frame comprises uprights l0, along which extends horizontal runs II, to which are secured tentering hooks or clips, (not shown), for catching the side edges of the passes of the web of material l2. This general construction is well-known.

The tentering frame is suitably housed in an enclosure provided with side walls l3 and I4, end walls [5 and I6 and a top, for convenience, (not shown). This enclosure is located in a room of the mill or factory and provides that the heated air, to which the web of material is subjected, is not directed into the room, with resulting discomfort to room occupants, and heat and air current losses from the tentering frame and the web of material thereon.

Located at one side of the tentering frame is one of the passes of Web material.

s application March 2,

a conduit 34, (Fig. 4), connected to some suitable source of conditioned air. Connected to the conduit 34' is a branch conduit 35 terminating in vertical spaced relationship adjacent a face of Connected to the branch conduit 35 is a diifuser for discharging, against an associated pass or passes of the web of material, air, suitably conditioned, delivered into the conduit 34. These diffusers may be of two types, one discharging air in one direction, vertically upwardly or downwardly, and the other discharging air in opposite directions, vertically upwardly and downwardly. As the latter kind of diffuser may be considered as two of the single type secured together back to back, it is considered desirable to describe in detail only the double type of diffuser.

Considering the diffusers in detail, it has been stated above that the diffuser is adapted to discharge air in opposite directions, both upwardly and downwardly. Viewing Fig. 4, it should also be stated that the diffuser is adapted to discharge air both to the right and to the left, that is, in opposite directions laterally. The diffuser is located more or less centrally of the web pass along its length, thereby providing that the air discharged will travel generally lengthwise of the pass towards its opposite ends.

The diffuser is very roughly Y-shaped, and is provided with side walls 36, a flat top 31, and a flat bottom 38 parallel to the top. The top 3! and the bottom'38 are of the same shape and extend three quarters or more of the way across the web material, branching out beyond the midway point into right and left hand portions, as shown in Fig. 4. The side walls 36 extend only a short distance over the web material and with the top 3'! and bottom 38 form a neck 39 for connection with the branch air conduit 35. At their outer ends, the side Walls 36 are curved outwardly, as shown at 40. Extending centrally between the side walls 36 and connected to the top 31 and the bottom 38 is a vertical partition 4|, (Figs. 2 and 4), which extends along the top and bottom of the diffuser to the point where it branches off into right and left hand portions, at which point the partition 4| is joined to vertical walls 42 and 43 which form a V and are joined to the edges of the top and bottom of the diffuser. As shown in Fig. 4, the apex of the V formed by the walls 42 and 43 is directed inwardly.

In the construction just described, it will be seen that the diffuser comprises a conduit extending part way across the web material and provided with branches disposed away from each other and in the general direction of the opposite ends of the web pass. By reason of this construction, air driven into the branch conduit 35 and from there into the diffuser is guided by the side walls 36, the top 31, the bottom 38, the partition 4|, and the walls 42 and 43 into currents directed generally in opposite directions.

Viewing Fig.2, it will be seen thatif the partition 4| were the only deflector intermediate the side walls 36 and if the walls 42 and 43 were alone relied upon to direct the air over the web material, the air in the neck 39 would tend to pursue a straight course through the diffuser until deflected by the walls 42 and 43. This would obviously result in an uneven distribution of air over the webmaterial, the portions thereof adjacent the walls 42 and 43 receiving the greater part of the air, and the portions of the material adjacent the side walls 36 receiving the least air. This uneven distribution of air would cause uneven drying of the web material.

To offset this tendency for-uneven air distribution, the diffuser is provided interiorly iatweach side of the partition 4| with vertical vanes or bafiles 4-4, 45 and 46, best shown in Fig. -2. The ends of these vanes adjacent the neck-39 are aligned with the end of the partition -4|, and the vanes are spaced'from each other'andfrom the partition 4| and the side wall 36. 'Ihevane 44 has a curvature corresponding generally to that of the curved portion 4|] of the wall 36-and extends throughout slightly'more than 90 degrees, so that air passing between it 'and the wall curve 46 is directed slightly rearwardly towards the edge of the associatedpass of material, rather than directly longitudinally thereof. The vanes-45 and46 control the path of the air between the vane 44 and the walls 42 and 43 and function to change the pathof portions ofthe air at points ahead of the walls'42 and 43.

Preferably, the vanes -45 and 46 terminate short of the edgesof the diffuser top-31 and! bottom 3'8, so that pivoted deflectors may be associated with these vanes. Referringto Figs. 2 and 3, adjacent the frontends of the vanes '45 and 46, the diffuser is provided with vertical pins 41 on which are rotatably =moun'ted -vertical deflectors 48 forming, in effect, adjustable continuationsof the vanes 45 and 46. With this construction, the deflect-ors48 serve to regulate the paths of the air'emitting'from between-the vanes 44 and 45, 45 and 46, and46 and therpartition 4| and the wall -'42 -(or'4-3),ia.nd'so make it possible to have a more-even discharge of air from the diffuser than'if merely stationarywanes were used. Stated in another Wayfthe deflectors 48 form partitions or'dividers, as it were, for the opening bounded by the top 31,th'e bottom 38, the side wall 42 (or 43), "and the vane 44. Since the deflectors '48 are'pi-vot'ed, they may be turned to vary'the size of'the discharge ends of the passages betweenthe wall 42 (or '43) --and the vane 46, between the vane 46 and the'van'e 45, and between the vane 45 and the vane 44.

The construction so far described'provides fo'r auniform distribution of conditioned a-iriacross the passes of material from oneside thereof to the other and in opposite directions longitudinally thereof. It will be apparent,however, that without further air guiding means than those above described, the air would be discharged from the diffusers in a direction parallel to the passes of the web material. Such {a mode of operation would have a low efficiency, because a considerable quantity of the air would not come into contact with the passes, and hence would not absorb moisture. In order to provide for the greatest efliciency, the present invention contemplates that the air, in addition to being divided into two oppositely disposed currents by means of the partitions 4| and the walls, vanes, and deflectors associated therewith, shall also be further divided into currents directed upwardly and downwardly, so that all the air strikes against the passes of material, and not just a portion of the air.

For this purpose, the discharge ends of the =diffuser'are partially closed off between the top .31 .andthe bottom 38 by V-shaped deflectors Maud-50, (Figs. 1., 2 and 3) The walls 5| and 52 forming-the '-V "s are preferably curvilinear in cross section, with the apex of the Vs directed inwardly of the diffuser. The deflector 49 extendsbetween the'wall 43 (or 42) and the outer end of the vane 44 asshown in Fig. 2, while the deflector 50,'-which is shorter than thedeflector 49, extends between the outer end of the vane 44 and the end of the curved portion 40 of the side wall-36. Thedeflectors'fl and 50 are dis.- posed to each other at an angle of slightlymore than degrees, (Fig.2) and are provided with ends 53 and 54, respectively Referring to Figs. l-and 3-parti0ularlythe latter, the curved walls 5l-extendupwardly to a point slightly'below the plane of the diffuser top 31, thereby, with the ends 53 and the top 31, defining for thedeflector -49 arectangular opening 55 and for the deflector 50 a rectangular opening 56, both of which openings are located adjacent a pass of the web materiaL-and through which air is discharged "against the'pass. Similarly, the curved walls 52 .extenddownwardly to apoint slightly above the plane of the diffuser bottom 38, thereby, with the ends 54-and the bottom 38, defining-for the deflector -49 arectangular opening 51 and for the deflector 50 a rectangular opening 58 both of which openings are located adjacent the next succeeding lower pass of the material and through which air is discharged againstthe pass. Itwill be seen that with the above-described construction, the curved walls 5| and 52 guide the air-in the diffuser upwardly and downwardly, respectively, and that the plane of the rectangular openings 55, 56, 51 and 58 are all inclined to the'plan'es of -the-passes of web material, thereby causing the air discharged from the openings to :strike the passes of material obliquely.

The-diffuser =is "interposed between two adjacent passes of the web material and is, therefore, construct'ed-to discharge air both upwardly and downwardly. The-obliqueness of the planes of th'erectangulardifiuser openings to'the planes of the passes insuresthat all the air discharged strikes thepasses and does not issue from the diffuser 'in a path "parallel to the passes. The curved walls 36, the -V-walls 42 and 43, the vanes 44, 4-5 and 46, the deflectors 48, and the disposition of the rectangular diffuser openings angularly to'each other insure by their cooperation that the air admitted into the neck '39 is spread evenly across-the width of the passes of material. Upon issuing from. the diffuser, the impelled air strikes the adjacent faces of the passes and-spreads therealong, both along their length and also from one side edge thereof to the other. In effect, the discharged air-forms a constantly moving blanket --cover ing the entire faces of the passes and absorbing moisture therefrom as the air moves.

The passes of web material are relatively long and sag to a certain extent between their points of support in the tentering frame. As the diffusers and collectors, both single and double type, are positioned closely adjacent the passes, it is advisable to provide the diffusers with suitable guides, so that the web does not catch on projecting points or edges. These guides comprise curved bands 86, the free ends of which are connected to the top 31 and the bottom 38 of the diffuser, so that the curved portion of the band extends outwardly from the diffuser. As shown in Fig. 1, one band is located near the V-wall 43 and the other band is located so as to extend between the adjacent ends 53 and 54 of the deflectors 49 and 50. It will be understood that both the right and left hand portions of the double diifusers are provided with guides 86. With these guide constructions, the passes of the web material cannot contact sharp corners or edges and are thus protected from injury during their travel through the tentering frame.

In view of the foregoing, it is believed that the operation of the illustrated embodiment of the present invention will be readily understood. Air which is conditioned is impelled into the main conduits leading to the diffusers, from which it is discharged evenly and uniformly against the adjacent passes of web material. The portion of the material which dries slowest determines the rate at which the web isrun through the machine, and since the discharged air is spread uniformly over the passes, there is no opportunity for uneven drying and shading eifects. Since the air does not travel through the material, because of the texture thereof, the air travels over the material to its side edges, insuring their drying as completely as that of the interior portion of the material away from its side edges. After travelling over the side edges of the material, the air is collected by the various collectors and is conveyed away.

It may be advisable to provide the ends of the passes as well as their mid portions with a diffuser, so that the passes can be subjected throughout their length to the influence of heated air and so that this influence will be substantially uniform throughout the entire surfaces of the passes. For this purpose, at the left hand end of the passes, viewing Fig. 4, there is provided a diffuser, and a similar provision is made at the right hand end of the passes.

These two systems are identical in all respects with the centrally located diffuser, with the one exception that they are single. Stated in another way, the single diffuser atthe left in Fig. 4 has the same shape as the right hand portion of the double diffuser and the right hand single diffuser in Fig. 4 has the same shape as the left hand portion of the double diffuser.

The left hand diffuser, (Fig. 4), receives air from a conduit 82, while the right hand diffuser receives air from a conduit 84. These conduits may receive conditioned air either from the same source of supply for the conduit 34 or from a duplicate source of supply of conditioned air.

Nothing herein explained is to be interpreted as limiting the present invention in the scope of its application to use in connection with the particular apparatus or particular mode of oper; ation or both selected for purposes of illustration and explanation. It will be apparent that the present invention is capable of use with web conveyors other than tentering frames, and with web materials other than textile fabrics. While the particular construction herein set forth is well suited to one mechanical form of the invention, it is not limited to these details of construction, nor to the conjoint use of all its features, nor is it to be understood that these particulars are essential, since they may be variously modifled within the skill of the artisan without departing from the true scope of the actual invention, characterizing features of which are set forth in the following claim by the intentional use of generic terms and expressions inclusive of various modifications.

What is claimed as new, is:

A diffuser for discharging impelled air having, in combination, a body portion comprising a top, :a bottom, and walls joining the top and bottom to form a conduit having an intake end and a discharge end offset therefrom, at least one vane extending along the body portion spaced from the walls for guiding the impelled air from the inlet end towards the ofiset discharge end, a deflector pivotally associated with the vane adjacent the laterally offset discharge end for deflecting the guided air, and means for dividing the deflected air into a plurality of oppositely disposed currents in directions substantially normal to the direction of the deflected air after its passage from the influence of the deflector.

CHARLES P. BRIDGES. 

